<PAGE>
 
                       Amendment to Employment Agreement

     This Amendment dated this 19th day of February 1998 amends that certain
Employment Agreement dated October 1, 1997, by and between Vitalink Pharmacy
Services, Inc. ("Employer" or "Vitalink") and Robert W. Horner, III ("Employee")
(the "Employment Agreement"), a copy of which is attached hereto as Exhibit A.
The terms of said Employment Agreement are hereby amended as follows:

     1.   Paragraph 2 is amended and restated as follows:

          "2.  Term.  Subject to the provisions for termination hereinafter
               provided, the term of this Agreement shall begin on the date of
               this Agreement and shall terminate on January 23, 2001.  Upon
               expiration of said period, the parties may extend the term if
               they mutually agree to do so."

     2.   Paragraph 3(a) is amended and restated as follows:

          "a)  Salary.  As of February 1, 1998, a base salary of One Hundred
               Forty Eight Thousand Dollars ($175,000.00) per annum payable in
               accordance with Employer's standard payroll practices from time
               to time in effect.  Such salary shall be reviewed annually and
               may be increased in accordance with Employer's standard
               practices."

     3.   The following is added as Paragraph 10(e):

          "e)  Change of Control.  Regardless of any other provision in this
               Agreement to the contrary, in the event of a Change in Control
               (as that term is defined hereinafter) of Vitalink, Employee shall
               be entitled to two (2) years, or the remaining period of this
               Agreement (as of the consummation of such Change in Control),
               whichever is greater, of the full amount of all potential
               compensation and benefits set forth in Paragraph 3 hereof (as are
               in effect at the time of the consummation of such change in
               control), excluding future stock option grants.  A lump sum
               payment representing the total of such compensation and benefits
               shall be made at the time of the consummation of such Change of
               Control.  This provision, however, is applicable only in the
               event that the Employee is not offered a comparable employment
               contract (i.e., same compensation, title, duties, authority,
               responsibilities, term and location) with the post-Change of
               Control entity as of the time of the consummation of such Change
               of Control.

               For purposes of this Paragraph 10(e), a Change in Control of
               Vitalink shall occur upon the happening of the earliest to occur
               of the following:

                    (i) any "person" as such term is used in Sections 13(d) and
               14(d) of the Securities Exchange act of 1934 ("Exchange Act"), as

<PAGE>
 
               amended, (other than (1) Vitalink, (2) any trustee or other
               fiduciary holding securities under an employee benefit plan of
               Vitalink, or (3) any corporations owned, directly or indirectly,
               by the stockholders of Vitalink in substantially the same
               proportions as their ownership of Stock (each an "excluded
               person")) becomes the "beneficial owner" (as defined in Rule 
               13d-3 under the Exchange Act), directly or indirectly, of
               securities of Vitalink representing 30% or more of the combined
               voting power of Vitalink's then outstanding voting securities;

                    (ii) the stockholders of Vitalink approve a plan of merger,
               consolidation, complete liquidation of Vitalink or an agreement
               for the sale or disposition by Vitalink of all or substantially
               all of the Vitalink stock and/or assets, or accept a tender offer
               for substantially all of Vitalink's stock (or any transaction
               having a similar effect);

                    (iii) individuals who were members of the Vitalink Board
               immediately prior to a meeting of the stockholders of the Company
               involving a contest for the election of Directors do not
               constitute a majority of the Vitalink Board immediately following
               such election, unless that election of such new Directors was
               recommended to the stockholders by Vitalink management.

     4.   With the exception of the specific amendments set forth above, all
          terms and conditions of the Employment Agreement remain in full force
          and effect.

     IN WITNESS WHEREOF, the parties have executed this Agreement on the date
first set forth above.

Attest:                                      Employer:
                                             VITALINK PHARMACY SERVICES, INC.


/s/ Jeanne M. Barlett                        /s/ Donna L. DeNardo
---------------------------------------      ----------------------------------
Jeanne M. Barlett, Assistant Secretary       By:  Donna L. DeNardo, President
                                                  & Chief Operating Officer


Witness:                                     Employee:


/s/ Jeanne M. Barlett                        /s/ Robert W. Horner, III   
---------------------------------------      ---------------------------------- 
                                             Robert W. Horner, III
                                             Senior Vice President, General
                                             Counsel & Secretary